Perception and Watts: Doubling of power

Turn on your I phone SPL meter and let me know when you get to 140 decibels.

We can easily distinguish changes in loudness but human beings are not SPL meters - our sensory system doesn't work that way in the sense of being able to calibrate what we hear in dB - cue the eleven is one louder sketch in Spinal Tap.

As regards the reference to amplifier power in the OP. I don't think many people look for more powerful amplifiers from the perspective of playing louder. It's more about dynamic range and playing at the desired volume level without distortion.

Speaking of distortion, a low wattage amplifier driven into clipping will sound subjectively louder than a high power amplifier playing at equivalent or lower SPLs.

As another example, modern popular music which has been compressed to hell sounds superficially louder - hence the loudness wars in modern mastering.

So loudness is a bit of an ephemeral concept.

50 W difference isn't really that much - unless the user is pushing the lower powered amp into clipping.  Clipping results in increased high frequency content, harsher sound, and possible damage to speakers and/or amp.

Playing loud and watts seldom comes into the picture in… well non-low end systems (ok, maybe for college parties). Unless there is a gross mismatch in sensitivity and power.

More power tends to add weight and realism to the sound you get… it fills it out more than making it louder.

I have Audio Research Ref160 monoblocks, they can be run in linear (140wpc) or in triode mode (70 wpc)… there is no obvious difference in volume what so ever. I was actually surprised… I was listening for solidity, but thought I would hear a difference. The only difference I heard was in the ultra linear mode the treble became a bit hard and some of the midrange bloom dried up. I operate them in the triode mode, and they can play at deafening sound levels… (a dealer came over to listen and cranked them… wow, that was loud).

In solid state amps the power directly transforms itself into slam… that is one of the reasons high power ss amps are prized.

I only feel like I have scratched the surface. We’ll see if anyone wants to continue.

@ghdprentice 

Good ear. Triod is much better on my canary monoblocks as well exactly the difference  you found with you audio reseach